Moved theme related state from BrowserInstantController to InstantService.

chrome/common/instant_types.cc

 // Copyright 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/common/instant_types.h"
 
 InstantSuggestion::InstantSuggestion()
     : behavior(INSTANT_COMPLETE_NOW),
       type(INSTANT_SUGGESTION_SEARCH),
       autocomplete_match_index(kNoMatchIndex) {
@@ skipping 16 matching lines @@
 
 InstantAutocompleteResult::InstantAutocompleteResult()
     : transition(content::PAGE_TRANSITION_LINK),
       relevance(0) {
 }
 
 InstantAutocompleteResult::~InstantAutocompleteResult() {
 }
 
 ThemeBackgroundInfo::ThemeBackgroundInfo()
-    : color_r(0),
-      color_g(0),
-      color_b(0),
-      color_a(0),
-      image_horizontal_alignment(THEME_BKGRND_IMAGE_ALIGN_CENTER),
-      image_vertical_alignment(THEME_BKGRND_IMAGE_ALIGN_CENTER),
-      image_tiling(THEME_BKGRND_IMAGE_NO_REPEAT),
+    : color_r(-1),
+      color_g(-1),
+      color_b(-1),
+      color_a(-1),
+      image_horizontal_alignment(THEME_BKGRND_INVALID_ALIGNMENT),
+      image_vertical_alignment(THEME_BKGRND_INVALID_ALIGNMENT),
+      image_tiling(THEME_BKGRND_INVALID_REPEAT),
       image_height(0),
       has_attribution(false) {
 }
 
 ThemeBackgroundInfo::~ThemeBackgroundInfo() {
 }
+
+void ThemeBackgroundInfo::Initialize() {

[samarth, 2013/06/19 00:14:36]

I don't like having a Initialize method on a struct. This should just be the
default constructor.

[kmadhusu, 2013/06/19 02:27:24]

SearchTabHelper tracks |last_known_theme_info_|. Whenever a navigation entry is
committed, I want to invalidate |last_known_theme_info_|. I don't want to
invalidate the member values in SearchTabHelper.

Instead of defining a behavior to invalidate the member variables, I thought it
would be better if the default constructor initializes the member variables with
invalid values and then the caller can initialize the object using Initialize()
function. As per Google C++ style guide, a struct can have Initialize() function
(Ref:
http://google-styleguide.googlecode.com/svn/trunk/cppguide.xml?showone=Struct...).


Do you prefer to have an Invalidate() on a struct? 

+  color_r = 0;
+  color_g = 0;
+  color_b = 0;
+  color_a = 0;
+  theme_id = std::string();
+  image_horizontal_alignment = THEME_BKGRND_IMAGE_ALIGN_CENTER;
+  image_vertical_alignment = THEME_BKGRND_IMAGE_ALIGN_CENTER;
+  image_tiling = THEME_BKGRND_IMAGE_NO_REPEAT;
+  image_height = 0;
+  has_attribution = false;
+}
+
+bool ThemeBackgroundInfo::IsValid() const {
+  bool valid_image_details =
+      image_horizontal_alignment != THEME_BKGRND_INVALID_ALIGNMENT &&
+      image_vertical_alignment != THEME_BKGRND_INVALID_ALIGNMENT &&
+      image_tiling != THEME_BKGRND_INVALID_REPEAT &&
+      image_height > 0;
+
+  return color_r >= 0 && color_r <= 255 &&
+      color_g >= 0 && color_r <= 255 &&
+      color_b >= 0 && color_b <= 255 &&
+      color_a >= 0 && color_a <= 255 &&
+      (theme_id.empty() ^ valid_image_details);
+}
+
+bool ThemeBackgroundInfo::operator==(const ThemeBackgroundInfo& rhs) const {
+  return color_r == rhs.color_r &&
+      color_g == rhs.color_g &&
+      color_b == rhs.color_b &&
+      color_a == rhs.color_a &&
+      theme_id == rhs.theme_id &&
+      image_horizontal_alignment == rhs.image_horizontal_alignment &&
+      image_vertical_alignment == rhs.image_vertical_alignment &&
+      image_tiling == rhs.image_tiling &&
+      image_height == rhs.image_height &&
+      has_attribution == rhs.has_attribution;
+}